The investigator has developed a novel cell -free system based on extracts from eggs of the frog, Xenopus laevis. Such egg extracts are able to reproduce many of the features of apoptosis, including chromatin condensation, endonucleolytic DNA cleavage and the shrinkage and fragmentation of the nuclei. Lysates from baculovirus-infected cells expression the oncogene bcl-2 can suppress nuclear fragmentation. This system provides an excellent means to dissect the molecular mechanisms of apoptosis and protective function of bcl-2. The applicant proposes to identify and characterize some of the cytoplasmic events of apoptosis. Such cell-free systems offer the opportunity to reconstitute the apoptotic process from fractionated components.